The present invention relates to a drying machine for drying clothes or the like contained in a drying chamber. Especially, the drying machine has a preset function, by which the time when a drying operation is to be completed can be set in advance.
A prior drying machine is disclosed, for example, in Japanese Laid-Open Patent Application 64-85698. To use a preset function, the user sets a time when the user wants the drying machine to complete its drying operation, by using a keyboard. When the user presses a start switch to start the preset function, the drying machine begins counting. A display indicates an actual time before the drying operation starts. The drying machine automatically starts the drying operation a predetermined time prior to the set time. The predetermined time is decided based on a maximum capacity of the drying machine, for example, five hours.
In the drying operation, the display indicates a rest time when the clothes in the drying chamber are dried. The drying machine has a detector of degree of dryness of clothes. When the drying operation of clothes progresses and the degree of dryness has reached a predetermined value, for example, 95%, a heater and a fan are deenergized.
In most cases, the drying operation is actually completed prior to the set time. After the drying operation is completed, a finishing operation starts twenty minutes prior to the set time. In the finishing operation, a power of the heater is reduced to half in comparison with that in the drying operation. The finishing operation is stopped at the set time.
However, the inventor of the present invention has noticed that a case can occur, where although the set time is up, the degree of dryness does not reach the predetermined value. In this case, the drying machine continues to dry the clothes until the degree of dryness reaches the predetermined value. At the set time, the display indicates zero which indicates that the drying operation is completed.
As a result, the user may misunderstand the indication, and believe that the drying operation is completed. The user might then open a door to remove clothes from the drying chamber. When the user opens the door, the drying operation is stopped but the clothes are not sufficiently dried.
Especially, in the type of drying machine in which after the finishing operation is completed, the heater heats clothes to maintain a warmness thereof, so-called soft keep operation, the user can easily misunderstand. That is, even though after the drying operation is completed the drying machine does not stop. Therefore, it is difficult for the user to determine whether the drying operation is completed.